1. Field of the Invention
The present invention relates to a semiconductor device for use in a sense amplifier of a memory circuit. Particularly, it relates to a differential amplifier for amplifying the difference in potential between a data signal and a reference voltage.
2. Description of the Prior Art
Generally, in a metal-oxide semiconductor (MOS) static memory circuit, a sense amplifier and an output buffer are provided at the output portion thereof. The sense amplifier usually consists of one or more stages of differential amplifiers, including a differential amplifier for amplifying the difference in potential between a data signal and a reference voltage.
The conductance g.sub.m of an MOS transistor decreases as the temperature increases. Therefore, a high level, i.e., an on-output level, of the output buffer, obtained from an output of the differential amplifier, has a negative temperature coefficient. A change in the on-output level of the output buffer creates a serious problem in a circuit such as an emitter-coupled logic (ECL) circuit.